Clipping Mask

by JakobJingleheimer

HTML

<ul class="mask-container list-inline list-justified">
    <li class="mask-window">
        <img src="//placehold.it/400/c42" />
    </li><!--
    --><li class="mask-window">
        <img class="mask-item" src="//placehold.it/400/a4c" />
    </li>
</ul>

CSS

body {
    padding: 10px;
}

.mask-container {
    position: relative;
}
.mask-window {
    overflow: hidden;
    position: static;
}
.mask-item {
    display: block;
    left: 50%;
    position: absolute;
    transform: translate(-50%, -50%);
    top: 50%;
}
.list-inline {
    list-style: none;
    margin: 0;
    padding: 0;
}
.list-inline > li {
    display: inline-block;
    padding: 0 0.25em;
    vertical-align: middle;
}
.list-inline > li:first-child {
    padding-left: 0;
}
.list-inline > li:last-child {
    padding-right: 0;
}
.list-justified {
    width: 100%;
}
.list-justified > li {
    display: table-cell;
    float: none;
    width: 1%;
}